Zerank 2 vs Cohere Rerank 4 Pro
Detailed comparison between Zerank 2 and Cohere Rerank 4 Pro. See which reranker best meets your accuracy and performance needs.
Model Comparison
Zerank 2 takes the lead.
Both Zerank 2 and Cohere Rerank 4 Pro are powerful reranking models designed to improve retrieval quality in RAG applications. However, their performance characteristics differ in important ways.
Why Zerank 2:
- Zerank 2 has 17 higher ELO rating
- Zerank 2 is 348ms faster on average
Overview
Key metrics
ELO Rating
Overall ranking quality
Zerank 2
Cohere Rerank 4 Pro
Win Rate
Head-to-head performance
Zerank 2
Cohere Rerank 4 Pro
Accuracy (nDCG@10)
Ranking quality metric
Zerank 2
Cohere Rerank 4 Pro
Average Latency
Response time
Zerank 2
Cohere Rerank 4 Pro
Visual Performance Analysis
Performance
ELO Rating Comparison
Win/Loss/Tie Breakdown
Accuracy Across Datasets (nDCG@10)
Latency Distribution (ms)
Breakdown
How the models stack up
| Metric | Zerank 2 | Cohere Rerank 4 Pro | Description |
|---|---|---|---|
| Overall Performance | |||
| ELO Rating | 1644 | 1627 | Overall ranking quality based on pairwise comparisons |
| Win Rate | 58.3% | 58.2% | Percentage of comparisons won against other models |
| Pricing & Availability | |||
| Price per 1M tokens | $0.025 | $0.050 | Cost per million tokens processed |
| Release Date | 2025-11-18 | 2025-12-11 | Model release date |
| Accuracy Metrics | |||
| Avg nDCG@10 | 0.195 | 0.219 | Normalized discounted cumulative gain at position 10 |
| Performance Metrics | |||
| Avg Latency | 265ms | 614ms | Average response time across all datasets |
Dataset Performance
By field
Comprehensive comparison of accuracy metrics (nDCG, Recall) and latency percentiles for each benchmark dataset.
MSMARCO
| Metric | Zerank 2 | Cohere Rerank 4 Pro | Description |
|---|---|---|---|
| Accuracy Metrics | |||
| nDCG@5 | 0.491 | 0.562 | Ranking quality at top 5 results |
| nDCG@10 | 0.546 | 0.583 | Ranking quality at top 10 results |
| Recall@5 | 0.620 | 0.740 | % of relevant docs in top 5 |
| Recall@10 | 0.780 | 0.800 | % of relevant docs in top 10 |
| Latency Metrics | |||
| Mean | 233ms | 458ms | Average response time |
| P50 | 228ms | 408ms | 50th percentile (median) |
| P90 | 251ms | 615ms | 90th percentile |
arguana
| Metric | Zerank 2 | Cohere Rerank 4 Pro | Description |
|---|---|---|---|
| Accuracy Metrics | |||
| nDCG@5 | 0.283 | 0.353 | Ranking quality at top 5 results |
| nDCG@10 | 0.355 | 0.439 | Ranking quality at top 10 results |
| Recall@5 | 0.540 | 0.660 | % of relevant docs in top 5 |
| Recall@10 | 0.760 | 0.920 | % of relevant docs in top 10 |
| Latency Metrics | |||
| Mean | 280ms | 785ms | Average response time |
| P50 | 278ms | 768ms | 50th percentile (median) |
| P90 | 312ms | 933ms | 90th percentile |
FiQa
| Metric | Zerank 2 | Cohere Rerank 4 Pro | Description |
|---|---|---|---|
| Accuracy Metrics | |||
| nDCG@5 | 0.108 | 0.126 | Ranking quality at top 5 results |
| nDCG@10 | 0.119 | 0.129 | Ranking quality at top 10 results |
| Recall@5 | 0.098 | 0.130 | % of relevant docs in top 5 |
| Recall@10 | 0.130 | 0.135 | % of relevant docs in top 10 |
| Latency Metrics | |||
| Mean | 251ms | 610ms | Average response time |
| P50 | 254ms | 585ms | 50th percentile (median) |
| P90 | 270ms | 817ms | 90th percentile |
business reports
| Metric | Zerank 2 | Cohere Rerank 4 Pro | Description |
|---|---|---|---|
| Latency Metrics | |||
| Mean | 288ms | 529ms | Average response time |
| P50 | 269ms | 498ms | 50th percentile (median) |
| P90 | 367ms | 675ms | 90th percentile |
PG
| Metric | Zerank 2 | Cohere Rerank 4 Pro | Description |
|---|---|---|---|
| Latency Metrics | |||
| Mean | 293ms | 760ms | Average response time |
| P50 | 281ms | 720ms | 50th percentile (median) |
| P90 | 328ms | 896ms | 90th percentile |
DBPedia
| Metric | Zerank 2 | Cohere Rerank 4 Pro | Description |
|---|---|---|---|
| Accuracy Metrics | |||
| nDCG@5 | 0.138 | 0.151 | Ranking quality at top 5 results |
| nDCG@10 | 0.151 | 0.166 | Ranking quality at top 10 results |
| Recall@5 | 0.004 | 0.004 | % of relevant docs in top 5 |
| Recall@10 | 0.005 | 0.005 | % of relevant docs in top 10 |
| Latency Metrics | |||
| Mean | 247ms | 541ms | Average response time |
| P50 | 242ms | 489ms | 50th percentile (median) |
| P90 | 274ms | 729ms | 90th percentile |
Explore More
Compare more rerankers
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